My Place or Your Place?

A Little Background:
Girl: She is a very successful and a caring lady. She purchased a nice house (whose value has appreciated many folds) and being the only child, takes care of her parents.
Guy: Also very successful. As his parents are in a different city, he lives alone in a rented apartment.

If there was something like equality of sexes, then I would expect that after marriage, the guy gives up the rented place and they all live happily ever after in the house which his wife purchased out of her own hard earned earnings.

I agree that in older times when man was considered  a breadwinner, living off the wife’s wealth had a social stigma attached to it (it still has). However in this case both the spouses have a comfortable 7 digit salaries so nobody is dependent on the other. The parents earn sufficient from their pension and investments to take care of themselves and the house has more rooms than inhabitants, so privacy also should not be the issue.

Why is it that after marriage the girl has to move in to the guy’s place?